Hello, My configuration is Windows Server 2008 x64 R2 + SP1. I have problem related with backup (third party program). When I start backup I am getting Warning in Event log. Event ID: 12290 Description: Volume Shadow Copy Service warning: ESENT ERROR {b2014c9e-8711-4c5c-a5a9-3cf384484757} NTDS: -2402. hr = 0x00000000. and my VSS writer shows Writer name: 'NTDS' Writer Id: {b2014c9e-8711-4c5c-a5a9-3cf384484757} Writer Instance Id: {26ed439f-4a52-481d-963d-5db5b695d9e7} State: [10] Failed Last error: Retryable error I found soluton for Windows 2003 platform, but can not find solution for my OS platform. http://support.microsoft.com/kb/826936